[doc] Update Changelog for 3.1

Author: Wentzell

doc/ChangeLog.md

@@ -5,7 +5,39 @@
 ## Version 3.1.0
 
 w2dynamics_interface version 3.1.0 is a compatibility
-release for TRIQS version 3.1.0.
+release for TRIQS version 3.1.0 that
+* uses the latest [app4triqs/3.1.x](https://github.com/TRIQS/app4triqs) skeleton
+* switches documentation to read-the-docs theme
+* improves ghactions and jenkins configuration
+
+We thank all contributors: Alexander Hampel, Alexander Kowalski, Dylan Simon, Nils Wentzell
+
+Find below an itemized list of changes in this release.
+
+### General
+* After gcc stdlib update in <random> add reference data vor gcc version 11+
+* Manual porting to triqs 3.1 + nda + meshes
+* Adjust for new gf_struct type
+* Update to v1.1.1 of w2dynamics and update test ref files
+* Add worm_components parameter, limit test to subset of components
+* Make one-particle Green's function measurement optional
+* Add diagonalized version of two-orbital test for 2p-GF
+* Adapt to triqs 3, w2dynamics 1.1, and make code less redundant
+* Converter and solver interface for the two-particle Green's function
+* Use different ref test data when compiling with libcxx
+
+### doc
+* Add new parameters and short instructions on 2p-GF measurement
+
+### cmake
+* Let cmake of w2dynamics detect Fortran compiler
+* Clone from main w2dynamics repository and apply w2dynamics.patch
+* Detect use of libcxx through try_compile
+
+### CI
+* Enable ghactions builds for unstable
+* Specify BLAS_ROOT and LAPACK_ROOT for OSX builds
+* Build 2pgf branch against triqs/unstable
 
 
 ## Version 3.0.0